Tesis sobre el tema "Lawn Rangers"

3 pp.
Livestock are still an important part of rural life in Arizona. As more and more homes have been built adjacent to areas traditionally used for cattle grazing, the potential for conflict between livestock owners and homeowners has increased. Regardless of whether you yourself own large animals, you must be aware of your responsibilities towards your neighbors' livestock. The details of your responsibilities--and your liability--depend in large part upon where you live and whether you have a suitable fence around your property.

Darbe nagrinėjami šalių bendradarbiavimo pareigos vykdant statybos rangos sutartį teoriniai ir praktiniai aspektai. Pirmoje darbo dalyje siūlomas šios pareigos apibrėžimas, klasifikuojami pareigą sudarantys elementai, aptariama pareigos apimtis, ribos, reikšmė. Bendradarbiavimo pareiga statybos rangos atžvilgiu suprantama labai plačiai, kaip apimanti įvairaus pobūdžio šalių veiksmus, būtinus, kad būtų pasiektas statybos rangos sutarties tikslas. Antroji darbo dalis skirta praktiniams aptariamos pareigos aspektams ir su jais susijusioms problemoms aptarti. Šioje dalyje nagrinėjami šalių bendradarbiavimo pareigos klausimai susiję su statybos leidimo pateikimu, statybvietės sąlygomis, darbų atlikimu su užsakovo medžiagomis, projektinės dokumentacijos pateikimu ir pranešimu apie jos klaidas, neatitikimus, darbų perdavimu – priėmimu, darbų pakeitimais ir t.t. Darbe kritiškai vertinamas kai kurių statybos rangos sutarties sričių teisinis reguliavimas Lietuvoje, t.y. atsakomybės neproporcingas paskirstymas tuo atveju, kai darbai atliekami su užsakovo pateiktomis netinkamomis medžiagomis, atliktų darbų perdavimo – priėmimo kriterijai ir t.t. Analizuojami klausimai dėl užsakovo ir genrangovo teisės kontroliuoti darbus, o būtent tai, kad darbų kontrolė yra tapusi ne teise, o pareiga. Aptariami kiti veiksniai įtakojantys statybos rangos sutarties šalių bendradarbiavimą vykdant statybos rangos sutartį. Trečioje darbo dalyje pristatoma alternatyvi šalių bendradarbiavimą statybos rangos... [toliau žr. visą tekstą]
This master thesis analyses practical and theoretical aspects concerning the parties’ obligation to cooperate in the performance of a construction contract. The first part of the work proposes the definition of such obligation, discuses the extent and limits of this obligation, also classifies its elements. The parties’ obligation to cooperate in the performance of a construction contract is understood very broadly and includes all reasonable actions of a party necessary to be taken in order to achieve the goals of the construction contract. The second part of the work analyses the practical aspects of the obligation and the problems that surround it. This part particularly deals with the questions of the cooperation concerning the delivery of the permission to build, the site conditions, delivery of the design projects and the contractor’s obligation to warn about any discrepancies therein, taking over of the works and so on. The work presents a critical approach to some spheres of legal regulation in Lithuania, i.e. disproportion of the liability concerning the work done with inappropriate materials presented by the employer, the criteria of the works that have to be taken over and so on. Another point analysed is the right of the employer or the main contractor to control the works which has actually transformed into an obligation. Also other factors are analysed that have the influence on the cooperation between the parties in the performance of a construction contract... [to full text]

Magistro baigiamojo darbo tema – „Šalių atsakomybė statybos rangos santykiuose“. Raktiniai žodžiai: statyba, teisiniai statybos santykiai, statybos rangos santykiai, statybos rangos sutartis, subrangos sutartis, užsakovas, rangovas, subrangovas, atsakomybė. Sklandus ir efektyvus statybos proceso įgyvendinimas didžiąja dalimi priklauso nuo to, kaip aiškiai ir suprantamai statybos rangos sutartis ir teisės norminiai aktai apibrėžia sutarties šalių teises ir pareigas, paskirsto jų riziką bei atsakomybę už sutartinių prievolių netinkamą vykdymą. Atsižvelgiant į tai, darbe yra kompleksiškai analizuojami statybos rangos sutarties šalių atsakomybės pagrindai, nagrinėjamos problemas, susijusios su atsakomybės taikymu. Pirmojoje darbo dalyje atskleidžiama teisinių statybos santykių ir statybos rangos santykių samprata. Antrojoje dalyje apžvelgiama statybos rangos teisinius santykius reglamentuojančių teisės aktų sistema, pateikiamos statybos rangos santykių dalyvių sąvokos, atskleidžiamas jų teisinis subjektiškumas, nagrinėjama statybos rangos sutarties samprata ir jos esminės sąlygos, statybos rangos ir subrangos sutarčių santykis. Trečioji darbo dalis skirta išsamiai statybos rangos sutarties šalių – užsakovo, rangovo ir subrangovo – atsakomybės analizei: atskleidžiama jos specifika, taikymo pagrindai bei sąlygos, nagrinėjami atvejai, kai atsakomybė statybos rangos sutarties šaliai gali būti sumažinta arba panaikinta visa apimtimi, apžvelgiama LAT praktika, suformuota... [toliau žr. visą tekstą]
The subject of the master work – „The liability of the parties in legal construction relationship“. Keywords: construction, legal construction relationships, constuction contract, subconstruction contract, client, contractor, subcontractor, liability. Efficaciousness of the construction process for the most part depends on how clear and comprehensible the construction contract and legal acts define rights and obligations of the parties and divide between them risk and liability for an improper execution of the obligations. Taking it into consideration, in this work there is complex analysis of the legal basis for liability and problems, which are related to application of the liability. The first part of the work reveals conception of legal construction relationships. In the second part there is rewiev of the legal acts provided as well as the concepts of the parties.The author studies the conception of the construction contract, it‘s substantial conditions and relation between construction and subconstruction contracts. The third part of the work is committed to comprehensive analysis of the liability of the client, contractor and subcontractor: it reveals liability specific, basis and conditions of use, cases when liability can be reduced or avoided, provides the review of the Suprime Court of Lithuania practice, that was formed by solving cases for application of liability in legal construction relationships. The author, after accomplishing analysis of legal act... [to full text]

It is demonstrated that the method for locating a velocity profile origin, or plane of zero velocity, by fitting log profiles to streamwise velocity measurements is applicable to a larger range of roughness scales than previously expected. Five different sets of detailed, experimental velocity measurements were analyzed encompassing sediment-scale roughness elements, roughness caused by rigid vegetation, and large-scale roughness elements comprised of mobile bedforms. The method resulted in similar values of normalized zero-plane displacement for all roughness types considered. The ratios of zero-plane displacement, dh, to roughness height, ks, were 0.20 and 0.26 for the sediment- and vegetation-scale experiments, respectively. The results for the two experiments with bedform dominated roughness were 0.34 and 0.41. An estimate of dh/ks ranging from 0.2 to 0.4 is therefore recommended for a range of roughness types with the higher end of the range being more appropriate for the larger, bedform-scale roughness elements, and the lower end for the sediment-scale roughness elements. In addition, it is demonstrated that the location of the plane of zero velocity is temporally constant even when the bed height is not. The effects of roughness element packing density were also examined with the identification of a possible threshold at 4%, above which zero-plane displacement is independent of packing density. The findings can be applied to field velocity measurements under mobile bed conditions, facilitating the calculation of turbulence parameters such as shear velocity, by using point measurements and providing guidelines for the estimation of an appropriate value for zero-plane displacement.
Master of Science

Šiame magistro baigiamajame darbe mėginama sisteminiu požiūriu atskleisti, ištirti ir įvertinti rangos sutarties sampratos ir dalyko požymius, šios sutarties šalių, bei jų teisių ir pareigų teisinio reglamentavimo, įtvirtinto LR CK, įstatymuose bei teismų praktikoje, sąlygotas teorines ir ypač praktines problemas. Darbe analizuojami esminiai rangos sutarties požymiai ir turinio sąlygos, dėl jų įgyvendinimo, kylantys praktiniai klausimai. Akcentuojama, jog rangos sutarties šalys įgyvendindamos savo teises ir pareigas, kurios yra priešpriešinio pobūdžio, privalo bendradarbiauti. Rangos sutarties subjektinė sudėtis nagrinėjama, atsižvelgiant į užsakovo ir rangovo sutartinių santykių ypatumus. Taip pat aptariami klausimai, kylantys dėl subrangos sutarties šalių teisių ir įsipareigojimų pasiskirstymo bei atsakomybės, susijusios su nepakankama subrangovo darbų kontrole, ribų.
The purpose of this article is to introduce problematical questions of legal regulation of independent work contract parties, their rights and obligations. The author has analyzed special legal literature and concentrates on problems determinate of legal regulation of Civil Code of the Republic of Lithuania. The article also provides for the review of conditions of independent work contract prepared by FIDIC and recommended for general use in case of engineering and building construction contracts. Independent work contractor is responsible for the means and methods to be used in the construction of the project in accordance with the contract of independent work agreement. General independent work contractor involves subcontractors to fill in the additional areas of work. In the author’s point of view contracting parties are fully obligated cooperate and be carefully performing the work under contract. A separate part of the article analyses certain aspects of particular rights and obligations of contracting parties. The contractor is obligated to take all necessary measures to ensure that the result of works satisfies regulations containing essential requirements and standards of quality established under the contract. Moreover, the contractor is responsible for damages that occur as a result of the contractor’s fault, and he is obligated to protect property of customer. Therefore, the article tries to analyze the customer’s obligation to take the result of work from... [to full text]

This study focuses on the development of a new, formal method for the automated checking of pedestrian circulation rules in Courthouse Design Guide. Automated building rule checking is an automated process of design evaluation against design requirements. Since the early 1970's, when the electronic representation of building design became available, automated building rule checking, a computational process, has been a focus of study, and it continues to be a popular research area because it facilitates the design evaluation process by reducing the checking time and evaluation costs and by increasing the objectivity and the reliability of the evaluation. Thanks to the emergence of BIM (Building Information Model) authoring software, BIM became available to use in real building design, and several automated building code checking systems were developed based on BIM. In practice, the use of a rule checking system in real design evaluation may be influenced by several factors. Among the factors that affect the accuracy and the reliability of automated checking such as checking algorithms and rule interpretation is the level of completeness of the BIM in the design process, which can cause limitations in the application of a rule checking algorithm to the model. Problems caused by the incompleteness of the BIM occurred in CORENET project, a project initiated by the Singapore government in 1999 for automation of building code checking, and GSA Courthouse Design Guide Automation project (GSA), initiated at Georgia Tech in 2007 also faced with the same problems caused by incompleteness of BIM in the development stage. This thesis is a continuing research of GSA-Courthouse Design Guide Automation project (Simply, GSA project). The theoretical goals of this study are to provide a logical foundation upon which one can build an automated checking module for circulation rule checking and that is capable of outlining the rule-validation process independently from its diverse implementation. The theory for circulation rule checking is devised to represent the process of the validation of a building design in the development stage. The theory deals with issues of validation caused by the lack of data in the development of a building design.

In this work we develop a Blast-Propellant-Facility integrated analysis study, which evaluates, by using two different approaches, the blast-related impact of an explosive accident of the Space Shuttle during the first ten seconds after launch at Kennedy Space Center. The blast-related risk associated with an explosion at this stage is high because of the quantity of energy involved in both multiple and complex processes. To do this, one of our approaches employed BlastFX®, a software system that facilitates the estimation of the level of damage to people and buildings, starting from an explosive device and rendering results through a complete report that illustrates and facilitates the evaluation of consequences. Our other approaches employed the Hopkinson-Cranz Scaled Law for estimating similar features at a more distant distance and by evaluating bigger amounts of TNT equivalent. Specifically, we considered more than 500 m and 45,400 kg, respectively, which are the range and TNT content limits that our version of BlastFX® can cover. Much research has been done to study the explosion phenomena with respect to both solid and liquid propellants and the laws that underlie the blast waves of an explosion. Therefore our methodology is based on the foundation provided by a large set of literature review and the actual capacities of an application like BlastFX®. By using and integrating the lessons from the literature and the capabilities of the software, we have obtained very useful information for evaluating different scenarios that rely on the assumption, which is largely studied, that the blast waves' behavior is affected by the distance. All of this has been focused on the Space Shuttle system, in which propellant mass represents the source of our analysis and the core of this work. Estimating the risks involved in it and providing results based on different scenarios augments the collective knowledge of risks associated with space exploration.
M.S.
Department of Industrial Engineering and Management Systems
Engineering and Computer Science
Modeling and Simulation

The fundamental distinction made in Shiite legal epistemology is that between qaṭʿ (certainty) and ẓann (conjecture). Contemporary Uṣūlī epistemology maintains that in the juristic process of the derivation of Sharīʿa precepts, a mujtahid is prohibited to use any evidence that gives rise to mere ẓann. Rather, he must only use evidence that gives qaṭʿ of Sharīʿa precepts. Furthermore, this discourse distinctly argues that a mujtahid can also derive knowledge of Sharīʿa precepts through the ẓann al-khāṣ (especial conjecture) that is emanated from evidence that is ẓannī (conjectural) by nature but is substantiated by the Divine Lawgiver Himself through other qaṭʿī (certainty bearing) evidence. This understanding effectively curtails the derivation of Sharīʿa precepts to only the textual evidence of the Qurʾān and sunna, and in the present day this textualist dependency can be criticised for contributing towards the gulf that exists between traditional Shiite jurisprudence and matters that are pertinent to contemporary societies. In light of this, this study critically analyses the contemporary discourse of Uṣūlī epistemology and explores whether it has the potential to legitimise the epistemic validity and utility of a wider range of evidence in the juristic process of deriving Sharīʿa precepts. It essentially focuses on the strength and rigour of the epistemological underpinnings that are maintained in Uṣūlī legal theory, and by highlighting that these underpinnings and the underlying epistemic assumptions that are prevalent in contemporary Uṣūlī legal epistemology are rationally derived, this study explains how and why the Uṣūlīs have been led to rationally give preference to textual evidence over nontextual evidence. This study concludes that Uṣūlī legal theory has the potential to, and moreover is required to, undergo an epistemological paradigm shift that permits the acceptance of the epistemic validity of a wider range of evidence, other than just those that emanate qaṭʿ or ẓann al-khāṣ.

La tesi presenta una serie di risultati dell'analisi quantitativa sulla linguistica. Inizialmente sono studiate due fra le leggi empiriche più famose di questo campo, le leggi di Zipf e Heaps, e vengono esposti vari modelli sullo sviluppo del linguaggio. Nella seconda parte si giunge alla discussione di risultati più specifici sulla presenza di fenomeni di burstiness e di correlazioni a lungo raggio nei testi. Tutti questi studi teorici sono affiancati da analisi sperimentali, svolte utilizzando varie traduzioni del libro "Guerra e pace" di Leo Tolstoj e concentrate principalmente sulle eventuali differenze riscontrabili tra le diverse lingue.

International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada
As technology progresses we are faced with ever increasing volumes and rates of raw and processed telemetry data along with digitized high resolution video and the less demanding areas of video conferencing, voice communications and general LAN-based data communications. The distribution of all this data has traditionally been accomplished by solutions designed to each particular data type. With the advent of Asynchronous Transfer Modes or ATM, a single technology now exists for providing an integrated solution to distributing these diverse data types. This allows an integrated set of switches, transmission equipment and fiber optics to provide multi-session connection speeds of 622 Megabits per second. ATM allows for the integration of many of the most widely used and emerging low, medium and high speed communications standards. These include SONET, FDDI, Broadband ISDN, Cell Relay, DS-3, Token Ring and Ethernet LANs. However, ATM is also very well suited to handle unique data formats and speeds, as is often the case with telemetry data. Additionally, ATM is the only data communications technology in recent times to be embraced by both the computer and telecommunications industries. Thus, ATM is a single solution for connectivity within a test center, across a test range, or between ranges. ATM can be implemented in an evolutionary manner as the needs develop. This means the rate of capital investment can be gradual and older technologies can be replaced slowly as they become the communications bottlenecks. However, success of this evolution requires some planning now. This paper provides an overview of ATM, its application to test ranges and telemetry distribution. A road map is laid out which can guide the evolutionary changeover from today's technologies to a full ATM communications infrastructure. Special applications such as the support of high performance multimedia workstations are presented.

Magistro baigiamojo darbo tema - „Nuostoliai ir jų atlyginimas statybos sutartiniuose santykiuose“. Raktiniai žodžiai: nuostoliai, nuostolių atlyginimas, statybos rangos sutartiniai santykiai, statybos rangos sutartis, užsakovas, rangovas. Magistriniame darbe analizuojami statybos sutartiniai santykiai. Atsižvelgiant į tai, kad statybos ranga yra populiariausias statybos organizavimo būdas, darbe nagrinėjami santykiai, kylantys iš statybos rangos. Vartojimo ranga darbe nenagrinėjama. Statybos rangos sutartinių santykių pagrindas yra šalis siejanti sutartis. Nuostoliai sukeliami tada, kai viena iš šalių arba abi šalys neįvykdo arba netinkamai įvykdo sutartį. Pirmame skyriuje nagrinėjami bendrieji nuostolių klausimai tokie kaip, nuostolių sąvoka, rūšys, nuostolių atlyginimo sąlygos bei atleidimas nuo nuostolių atlyginimo statybos rangos sutartiniuose santykiuose. Antrame skyriuje nagrinėjami nuostolių ir jų atlyginimo ypatumai ikisutartiniuose statybos rangos santykiuose. Trečiame skyriuje analizuojami dažniausiai pasitaikantys statybos rangos sutarties pažeidimai, jų kilimo priežastys, nuostoliai, kurie kyla dėl sutarties pažeidimų, bei jų atlyginimas. Išanalizavus teisės aktus, teisės doktriną bei teismų praktiką, patvirtinami darbe nurodyti ginamieji teiginiai. Kadangi Lietuvoje nėra vieningos nuomonės, kokią atsakomybę taikyti ikisutartiniuose santykiuose, dėl to nuostoliai ne visada yra tinkamai atlyginami statybos rangos ikisutartiniuose santykiuose. Taip pat, autorė... [toliau žr. visą tekstą]
The subject of master work – „Damages and their compensation in construction contractual relations“ Keywords: damages, compensation for damages, construction contractual relations, construction contract, client, contractor. In this master work author analyses construction contractual relations. Consumer contract relations are not the object of analysis. The base of construction contractual relations is a construction contract. When one of contract parties or both parties breaches the contract that causes damages. In the first part author analyses general questions about damages. Damages concept, types of damages, conditions for damages compensation, releases from damages compensation in construction contractual relations. In the second part author analyses damages and their compensation in pre-contractual construction relations. The third part of the work is commited to analysis of the most common breach of construction contract, causes of breach of contract and also damages and their compensation in construction contractual relations. After accomplishing analysis of legal act, law doctrine and practice of Lithuanian Courts, author can prove defended statements. Since there is no consensus about what kind of liability should be in pre-contractual relations in Lithuania, damages in construction contractual relations are compensated wrongly. Also author confirmes that imperative duty to cooperate is one of the remedies to avoid damages or reduce existing damages to a minimum... [to full text]

The invasive species Saltcedar is affecting water and land resources throughout the western states of America. Because of great water use capabilities and other ecosystem detriments, Saltcedar has been targeted for treatment. For successful management of Saltcedar, individual landowners need to be aware of the costs and benefits of treating Saltcedar. Eleven of the most commonly reported treatment methods were evaluated for firm level economic feasibility. Evaluated on the basis of treatment cost, treatment effectiveness, Saltcedar water-use, and re-vegetation water-use, a production plan of ten years was created for each treatment method. Some treatment methods required re-treatment and were evaluated with re-treatments most commonly found in the literature. Of the treatment methods evaluated, five treatment methods were determined to be most feasible. Landowner valuation of environmental changes in the ecosystem brought on by Saltcedar is very important in the decision of which treatment method to implement. Personal valuation, over a period of ten years, will often determine which treatment methods are most cost efficient.

La première partie de la thèse étudie le diagramme de phase d’une généralisation de la chaîne de Kitaev qui décrit un système fermionique avec un pairing p-wave à long rayon qui tombe avec la distance ℓ comme 1/ℓα. On a analysé les lignes critiques, les corrélations et le comportement de l’entropie d’entanglement avec la taille du système. Nous avons démontré l’existence de deux régimes massifs, (i) où les fonctions de corrélation tombent exponentiellement à de courtes distances et comme puissance à de longues distances (α > 1), (ii) où elles tombent à puissance seulement (α < 1). Dans la seconde région l’entropie d’intrication d’un sous-système diverge logarithmiquement. Remarquablement, sur les lignes critiques, le pairing à long rayon brise la symètrie conforme du modèle pour des α suffisamment petits. On a prouvé ça en calculant aussi l’évolution temporelle de l’entropie d’intrication après un quench. Dans la seconde partie de la thèse nous avons analysé la dynamique de l’entropie d’intrication du modèle d’Ising avec un champ magnétique qui dépend linéairement du temps avec de différentes vitesses. Nous avons un régime adiabatique (de basses vitesses) lorsque le système évolue selon son état fondamental instantané; un sudden quench (de hautes vitesses) lorsque le système est congelé dans son état initial; un régime intermédiaire où l’entropie croît linéairement et, ensuite, elle montre des oscillations du moment que le système se trouve dans une superposition des états excités de l’Hamiltonienne instantanée. Nous avons discuté aussi du mécanisme de Kibble-Zurek pour la transition entre la phase paramagnétique et antiferromagnétique
In the first part of the thesis, we propose an exactly-solvable one-dimensional model for fermions with long-range p-wave pairing decaying with distance ℓ as a power law 1/ℓα. We studied the phase diagram by analyzing the critical lines, the decay of correlation functions and the scaling of the von Neumann entropy with the system size. We found two gapped regimes, where correlation functions decay (i) exponentially at short range and algebraically at long range (α > 1), (ii) purely algebraically (α < 1). In the latter the entanglement entropy is found to diverge logarithmically. Most interestingly, along the critical lines, long-range pairing breaks the conformal symmetry for sufficiently small α. This can be detected also via the dynamics of entanglement following a quench. In the second part of the thesis we studied the evolution in time of the entanglement entropy for the Ising model in a transverse field varying linearly in time with different velocities. We found different regimes: an adiabatic one (small velocities) when the system evolves according the instan- taneous ground state; a sudden quench (large velocities) when the system is essentially frozen to its initial state; and an intermediate one, where the entropy starts growing linearly but then displays oscillations (also as a function of the velocity). Finally, we discussed the Kibble-Zurek mechanism for the transition between the paramagnetic and the ordered phase

With over twenty thousand complaints reported annually to police of child sexual abuse in South Africa, specialist police nvestigators are practised at taking statements from child complainants. This thesis analyses the fit between actualpolice practice and that recommended by international best practice. Children are a special class of witness because of their inherent social, emotional, and cognitive immaturity, and they are universally acknowledged to be very difficult witnesses to interview without the interviewer lending a bias to the process and thereby contaminating the outcome. The first half of the thesis therefore provides a detailed account of the research basis of current international best practice and of the hallmarks of that best practice which result in reliable interview outcomes. The second half of the thesis presents a descriptive analysis of 100 police statements taken from children in the Eastern Cape who had been raped in the period between 2010 and 2012. The findings of the analysis are presented in detail and then compared to the best practice summarised from the international research.

Le « marché intérieur » est générateur de contrats internationaux intra et extra-européens. La multiplication de ces contrats nécessite un marché intérieur « espace de liberté, de sécurité et de justice ». Le règlement « Rome I », instrument de droit international privé communautaire, assure la liberté contractuelle et la sécurité juridique par l’élaboration de règles générales de conflit de lois. La volonté d’assurer la justice contractuelle a donné lieu pour sa part à l’élaboration de règles spéciales de conflit de lois, qui visent à protéger les contractants en situation de faiblesse sociale ou économique face à leur cocontractant partie forte. Le règlement « Rome I » a ainsi consacré des règles spéciales de conflit de lois protectrices des intérêts des travailleurs, des consommateurs, des passagers voyageant au départ ou à destination de leur pays de résidence, des preneurs d’assurance de risques de masse communautaires, ainsi que des distributeurs et des franchisés. Toutefois, le succès du marché intérieur impose de parvenir à établir un équilibre entre la justice contractuelle, la liberté contractuelle et la sécurité juridique, même dans le cadre des règles spéciales protectrices de conflit de lois. Cet équilibre ne peut être atteint que par des correctifs de proximité. Le correctif de proximité inséré dans le cadre des règles spéciales protectrices de conflit de lois participe non seulement à la fonction principale de la règle de conflit de droit, à savoir la désignation de la compétence du système juridique le plus étroitement lié au contrat, mais également à la création et au fonctionnement de ce marché intérieur espace de liberté, de sécurité et de justice
The “internal market" generates international contracts within and outside Europe. The proliferation of these contracts in fact requires an internal market established as an "area of freedom, security and justice". Regulation "Rome I", instrument of private international and European law, displays the purpose of ensuring the contractual freedom and legal security per elaborating general rules of conflict of laws. The will of the European legislator to ensure contractual justice within the internal market give rise thus, to special rules of conflict of laws that protect the contracting parties in a weak position face their co-contractor in dominant position. Regulation "Rome I" consecrates conflict of laws rules protecting the interests of certain contracting parties, that it considers that they are "weak parties"; they are the workers, the consumers, the passengers traveling to or from their country of residence, the policyholders of mass risks located on European territory, as well as distributors and franchisees. However, the success of the internal market requires achieving a balance between contractual justice, contractual freedom and legal security, even under protective special rules of conflict of laws. This balance can be achieved by correctives of proximity. The corrective of proximity inserted as part of the protective special rules of conflict of laws not only participates in the main function of the rule of law conflict, namely the designation of the competence of the legal system most closely related to the contract, but also to the establishment and operation of an internal market, area of freedom, security and justice

Les travaux présentés ici proposent des convertisseurs d’énergie à haut rendement et très large dynamique de tension d’entrée, c'est-à-dire capables de fonctionner avec un rendement énergétique élevé sur une plage de tension d’entrée étendue (typiquement de 9V à 200V). De multiples tensions de réseaux sont standards dans l’industrie : elles sont spécifiques à un domaine (aéronautique, ferroviaire, …) et dépendent de la source primaire d’alimentation électrique (batterie d’accumulateurs, génératrice, …). Au sein d’un équipement embarqué, plusieurs réseaux peuvent cohabiter : une alimentation principale 110V et une alimentation de secours sur batterie 12V, par exemple. Le besoin de convertisseurs large dynamique d’entrée est donc une réalité, mais il n’existe sur le marché que peu de convertisseurs capables de réaliser une dynamique d’entrée supérieure à dix. Dans un premier temps, nous avons étudié les enjeux et les problématiques liés à la large dynamique d’entrée, afin de mieux cerner les limitations des topologies de puissance classiques. Nous avons ensuite traité le cas d’une architecture de conversion d’énergie de type série, dont nous avons amélioré le rendement énergétique grâce à l’utilisation de circuits d’aide à la commutation. Cette solution ayant des performances limitées, nous avons proposé de nouvelles architectures de convertisseurs DC/DC, de type parallèle, capables de supporter des dynamiques de tension d’entrée supérieures à vingt et ayant un rendement énergétique élevé (supérieur à 80%). Nous avons également étudié et mis en œuvre des stratégies de commande, numériques et analogiques, permettant de contrôler ces nouvelles topologies complexes
Power converters are present in virtually every embedded system, but many standards of DC networks exist: the supply voltage is depending on how the power is generated (battery, alternator …) and can range from 12V to more than 115V. When an equipment must comply with a 110V main supply and 12V back-up supply, the use of a wide input voltage range DC/DC converter is mandatory. Since classical switched mode power converters cannot achieve simultaneously high efficiency and wide input voltage range, manufacturers rarely propose DC/DC converters with an input voltage range greater than 10. This work tackles the issue of wide input voltage power conversion. After discussing about designs trade off and problems that stem from a wide input range, we try to improve the overall efficiency of a classical buck-boost converter, by using non dissipative switching-aid circuits. We also proposed a novel two stages power converter capable of dealing with very wide input voltage ranges (more than 20), without a reduction of the power efficiency. Since those new converters are far more difficult to control, some theoretical analysis was performed and some practical tests were done using complex controls laws

碩士
國立臺灣大學
地質科學研究所
105
Southern Taiwan, including Pingtung peninsula and Taitung, is the incipient oblique convergent zone of Eurasian plate and Philippine Sea plate. Subduction activity formed the Luzon volcanic arc and accretionary wedge offshore southern Taiwan. So that we can infer the incipient feature structure from the topography and outcrop study of southern Taiwan. Hengchun peninsula remained the structural evolution evidence about Taiwan as subduction zone to orogenic zone inside the accretionary wedge. Previous studies observed some mountain building history by analyzing the antiformal syncline and shear zone by the tomography and field survey along the Taimali to Jinlun coastline Such as east-vergent structures which formed the overturned formation and left lateral faults which caused by transpression process. In this study, we continued the former studies and integrate the records of the structure from the field survey to complete the structure evolution story. The field survey of this study is in the Reserve area from Nantien to Syuhai, Southeast coastline of Taiwan, also known as A-Lan-Yi Trail, which preserving the ecological environment and biodiversity with abundant geological activity record. Furthermore, to map the distribution of regional structures with topography in this accessible area, I applied the 5m DTM (Digital Terrian Model) to mark the bedding attitudes with GPS data, then I adopted the true 3D model based on unmanned aerial vehicle-derived images to observe the inaccessible high area. Afterword, I use FaultKin to calculate the striation data for paleo-stress direction and divide it to different stages by the crosscutting relationship then compare the result with former studies. This study provides a strong evidence of back-thrusting and back-folding deformation during the incipient oblique collision stage, and as well as the discovered structures in this area show the similar kinematic history as the eastern flank of Central Range. Finally, after concluding the paleo-stress stages to above-mentioned results, I propose a possible evolution model with deformation history of this study area.

博士
中正理工學院
國防科學研究所
87
Inertial Navigation System(INS) is an autonomous, self-contained and non-radiating equipment suitable for navigation of military vehicles. However, the INS position errors grow with time, making it improper for long time navigation. Without using high precision inertial instruments, we can promote the INS and maintain its accuracy for long time operation by incorporating the Global Position System(GPS) into it. Building up an accurate error model of GPS and INS and well designing the Kalman Filter(KF) are critical to the successful integration of GPS and INS. From the practical point of view, too many KF state variables will increase the burden of navigation computer and the memory requirement. In this research, we omit some state variables concerning the inertial instrument biases and platform attitude errors. To compensate for the effect resulting from the model reduction, we strengthen the process noise of the velocity errors states. Numerical simulations and error covariance analysis are conducted and the results show that the reduced order KF is just as good as the conventional KF design. The guidance command of proportional navigation guidance(PNG) law is proportional to the line of sight rate(LOSR) of the missile and the target. Although the PNG features the ease of implement and robustness, it often tends to saturate the lateral acceleration at the final stage on the intercept which results in large miss distance, the PNG is considered only to be suitable for the target at the constant speed or low maneuver. At present, numerous advanced guidance laws have been devised by applying optimal theory and estimation theory to intercept targets with high maneuver. However, they adopted the spirit of PNG design. It is found that if the missile has large initial heading error or is fired in short range, the advanced guidance laws will have poor intercept performance. In this work, two new terminal guidance laws (called Modofied Aiming Point Guidance Laws and Aiming Line Rate Guidance Law) are developed for the air-to-air missiles. The collision course of the guidance laws is chosen as the line connecting the position of missile and the predicted impact point. The proposed guidance laws have features of short intercept time, low lateral acceleration at the final stage of engagement, small miss distance, and large firing envelop. The superior performance of these two guidance laws makes themselves attractive to the design of missile guidance of the next generation.

碩士
清雲科技大學
機械工程系所
96
In this thesis, the fuzzy controller is positioning the long-range piezoelectric actuated stage that is established by us and measuring the stage. The 4-9-9-14 piezoelectric actuator developed by our lab can combine the figure monitor software LabVIEW and the data-mining card NI PCI-6115 to obtain the precision position signal of the linear scale. The fuzzy controller is designed to reach the goal of positioning stage because of the non-linear condition of the piezoelectric actuator. In traditional, the method to position the piezoelectric actuator is changing the degree of voltage, but in this thesis, the different control concept will be offered. The real propellent voltage time of the unit time can be changed to control the displacement of the stage; furthermore, the precision of the position stage in this thesis is nanometer level First, the stage is positioned with a load condition and a no load condition, furthermore, the left and right distance should be immovable, by this experience, the step ability of the 4-9-9-14 piezoelectric actuator can be known. Second, the continuing chasing position of the stage can be tested after the first experience. The result shows that the most precise positioning degree of the stage can be 0.4 μm, and the average degree is under the 1 μm. In conclusion, the concept of controlling real propellent voltage time by fuzzy law can position the stage to a precise degree.

abstract: ABSTRACT Following the tragic events of 9-11, top Federal policy makers moved to establish the Department of Homeland Security (DHS). This massive realignment of federal public safety agencies also loosely centralized all U.S. civilian security organizations under a single umbrella. Designed to respond rapidly to critical security threats, the DHS was vested with superseding authority and broad powers of enforcement. Serving as a cabinet member, the new agency was administered by a secretary who answered directly to the President of the United States or the national chief executive. At its creation, many touted this agency as a new security structure. This thesis argues that the formation of DHS was not innovative in nature. Rather, its formation was simply the next logical step in the tiered development of an increasingly centralized approach to policing in the United States. This development took place during the early settlement period of Texas and began with the formation of the Texas Rangers. As the nation's first border patrol, this organization greatly influenced the development of centralized policing and law enforcement culture in the United States. As such, subsequent agencies following this model frequently shared a startling number of parallel developments and experienced many of the same successes and failures. The history of this development is a contested narrative, one that connects directly to a number of current, critical social issues regarding race and police accountability. This thesis raises questions regarding the American homeland. Whose homeland was truly being protected? It also traces the origins of the power to justify the use of gratuitous violence and the casting of particular members of society as the symbolic enemy or outsiders. Lastly, this exploration hopes to bring about a better understanding of the traditional directionality of the use of coercive force towards particular members of society, while at the same time, justifying this use for the protection of the rights and safety of others. It is hoped that the culmination of this work will assist American society in learning to address the task of redressing past wrongs while building more effective and democratic public security structures. This is of the utmost importance as the United States continues to weigh the benefits of centralized security mechanisms and expanding police authority against the erosion of the tradition of states' rights and the personal civil liberties of its citizens. Because police power must continually be monitored and held in check, concerns regarding the increasing militarization of civilian policing may benefit from an objective evaluation of the rise of centralized policing as experienced through the development of the Texas Rangers and rural range policing.
Dissertation/Thesis
M.A. History 2012

碩士
國立成功大學
航空太空工程學系
87
The trajectory for maximum range of glide of an unpowered projectile is one of the most important problems in the flight mechanics. In this thesis, the singular perturbation method (SPM) is used to derive the real-time guidance law for the maximum-range glide of an unpowered projectile. Two computers are used for hardware-in-the-loop simulation of the guidance law---one represents for the plant and the other the controller. Data transfer model and computation behavior are observed in this thesis. The results may be used as the basis for more advanced hardware-in-the-loop simulation.

碩士
大同大學
資訊工程學系(所)
92
In time series analysis, there have been many statistic models widely used; some models could estimate long memory. A new idea for analyzing time series is Detrended Fluctuation Analysis (DFA), which was originally developed for finding long-rage power-law correlations in DNA sequences. We apply DFA to Taiwan stock market for three categories of data: TAIEX (Taiwan Stock Exchange Capitalization Weighted Stock Index), the group indices aggregated from individual stock indices, and individual stock indices. The results show that long memory exists in most listed companies of Taiwan stock market for the cases when scaling exponent not equals to 0.5. However, the correlations detected from aggregated data series do not imply the correlation of original data series. Our findings are that the correlations detected from main index do not imply the same correlation of group indices and individual stock indices, but there are greater than half of group indices and individual stock indices following the same correlation with the main index.

碩士
國立清華大學
生醫工程與環境科學系
97
The ammonia purge-and-trap (P&T) preconcentrator system is a device to separate ammonia from complicated matrices, which combining the concept of purge-and-trap and ammonia stripping. After the P&T pretreatment, the collected sample from trap vessel would be analyzed by ortho- Phthaldialdehyde (OPA) fluoresce derivatization or ion chromatography. The main research purpose of this thesis is to widen the P&T preconcentrator’s linear range under the same efficiency to previous work. And to measure ammonia’s Henry’s law constant under different temperature and different sodium hydroxide concentration. To extend the linear range under the same efficiency, the following parameters should take into account：affect of ultrasound, purging time, volume of trap solution, the composition of trap solution and its concentration. The advanced system broaden its linear range about 3 order to 20 ppb~100 ppm, make it possible to deal with wide ammonia concentration samples. Furthermore, directly ammonia measurement in the purge vessel can verify this system is keep mass balance. Both measurements of ammonia’s KH from purge vessel and trap vessel are very close to the theoretical value and the reference ones. Therefore, this system can not only apply to the pretreatment of wide ammonia concentration samples but also measure ammonia’s KH precisely.

碩士
佛光人文社會學院
未來學研究所
91
Abstract Basing on the Methodology of Futurology and from the aspects of Cultural Futurology, Strategy Research of Public Policies and Tourism, this study will be undertaken in Documents Analyzing and General Interview Guide Approach. The observation schedule is from the end of August in 2002 to June in 2003, and the research schedule is from 2003/7 to 2007/6 in totally 5 years. This study will research in Arts Festival and International Arts Festival documents, cultural tourism developing mega-trends, entire tourism space in I-Lan, total space structure of Chinshui Water Park, Tungshan River, I-Lan, activities and efficiency analyzing, maturity tourism nucleus analyzing, tourism gains analyzing, SWOT analyzing, potential tourists in the future, limitations and the results of interview. After analyzing and reorganizing under the Methodology of Futurology, this study will have the conclusion that the future cultural drawing of “Merry, Hope, Children''s Paradise” is positively existing. And hoping to make the best strategies for the better future of I-Lan International Children''s Folklore & Folkgame Festival, this study will arrange 15 main concepts, 4 detailed developing strategy catalogues, and 3 suggestions for the subsequent researches to broaden the cultural views of Taiwan people, deepen total space aesthetics, establish the ideal model for Taiwan international arts festivals, and provide a new way for culture industry development and the entire vision of sustainable, successful management.

This study was directed at examining the effects of exhaust gas recirculation (EGR), water/N2/CO2 injections and oxygen enrichment on availability destroyed because of combustion in simple systems like those of constant pressure and constant volume. Higher cooled EGR fractions lead to higher availability destruction for reactant temperatures less than 2000 K. The availability destroyed for 40% EGR at 300 K for constant pressure and constant volume combustion was 36% and 33%, respectively. Neglecting the chemical availability in the products, the equivalence ratio and reactant temperature that corresponded to the lowest availability destruction varied from 0.8 to 1.0 and 800 K to 1300 K, respectively, depending on the EGR fraction. The fraction of the reactant availability destroyed increased with the complexity of the fuel. The trends stayed the same for the different EGR fractions for the eight fuels that were analyzed. Higher injected water fractions lead to higher availability destruction for reactant temperatures less than 1000 K. The availability destroyed for a 40% injected water fraction at 300 K for constant pressure combustion was 36%. The product temperature ranged from 2300 K to 450 K at a reactant temperature of 300 K for injected fractions from 0% to 90%. For a 40% injected fraction at a reactant temperature of 300 K, water injection and cooled EGR resulted in the greatest destruction of availability (about 36%) with CO2 injection leading to the least destruction (about 32%). Constant volume combustion destroyed less availability compared to constant pressure combustion at a reactant pressure of 50 kPa. At a higher reactant pressure of 5000 kPa, constant pressure combustion destroyed less availability compared to constant volume combustion for reactant temperatures past 1000 K. Higher fractions of oxygen in the inlet lead to higher product temperatures that lead to lower availability destruction. For 40% oxygen in inlet, the product temperature increased to 2900 K and the availability destroyed dropped to 25% at a reactant temperature of 300 K for constant pressure combustion.

Wächst eine Population und breitet sich dabei geographisch aus, so spricht man von räumlichem Populationswachstum, bzw. einer Range-Expansion. Viele Arten haben im Verlaufe ihrer evolutionären Geschichte ihr Verbreitungsgebiet ausgeweitet. Gründe hierfür können beispielsweise ein geändertes Klima oder die Verschleppung der Art in einen neuen Lebensraum sein. Während einer Range-Expansion können durch Gene-Surfing räumliche Verteilungen von neutralen genetischen Varianten entstehen, die den Folgen von selektiven Prozessen ähnlich sind. Für eine korrekte Interpretation der genetischen Daten ist daher die Kenntnis über quantitative Auswirkungen von Range-Expansions auf die genetische Vielfalt unumgänglich. In dieser Arbeit charakterisiere ich die Konsequenzen von Range-Expansions für Allelfrequenz-Spektren. Dazu generiere ich in Computersimulationen genetische Daten für unterschiedliche demographische Szenarien sowie diverse ökologische und geographische Bedingungen. Ich zeige, dass Range-Expansions innerhalb kurzer Zeit zu Allelfrequenz-Spektren führen können, die sich durch ein Potenzgesetz mit einem spezifischen Exponenten beschreiben lassen. Dieser Exponent liegt zwischen den erwarteten Exponenten für stabile und exponentiell wachsende, durchmischte Populationen. Mutationen, die während einer Range-Expansion aufgetreten sind, tragen meinen Ergebnissen zufolge weniger zu heutigen Allelfrequenz-Spektren bei, als Mutationen, die bereits in der Ursprungspopulation vorhanden waren. Allerdings eignen sich neue Mutationen besser, um Range-Expansions in genetischen Daten aufzuspüren, da sie weniger von geographischen Strukturen beeinflusst werden. Meine Resultate werden dazu beitragen, Spuren von Range-Expansions in genetischen Daten zu entdecken und Rückschlüsse auf die evolutionäre Vergangenheit von Populationen zu ziehen.

碩士
佛光人文社會學院
未來學研究所
91
Abstract In 2000, I-Lan held I-Lan Green Expo. for the first time. In comparison with other diverse festivals and expositions in Taiwan, I-Lan Green Expo. is the most creative and educational. After some adjustments in the second year, I-Lan Green Expo. finally showed out with the combination of Eco-Tourism concept and attracted thousands of tourists. This study, with I-Lan Green Expo. for example, is based on the methodology of futurology and from the aspects of Futurology, Tourism and Ecology. The Main methods of this study are Documents Analyzing, Field Observation, and Focus Interview Approach. The time schedule is from 2002/4 to 2003/3, and the research schedule is from 2003/3 to 2007/2, totally 5 years. In order to get the future strategies of I-Lan Green Expo., this study will be undertaken in using SWOT Analyzing Approach and trying to find out any possible way to draw the future developing vision. To sum up, this study will have a conclusion of 10 ways, 7 developing strategy plans, and 4 subsequent research directions to be the most useful and available future developing strategies of I-Lan Green Expo..

Τα κατανεμημένα δίκτυα κλίμακας Ίντερνετ και κυρίως τα δίκτυα ομοτίμων εταίρων, γνωστά και ως peer-to-peer (p2p), που αποτελούν το πιο αντιπροσωπευτικό παράδειγμά τους, προσελκύουν τα τελευταία χρόνια μεγάλο ενδιαφέρον από τους ερευνητές και τις επιχειρήσεις λόγω των ιδιόμορφων χαρακτηριστικών τους, όπως ο πλήρης αποκεντρωτικός χαρακτήρας, η αυτονομία των κόμβων, η ικανότητα κλιμάκωσης, κ.λπ. Αρχικά σχεδιασμένα να υποστηρίζουν εφαρμογές διαμοιρασμού αρχείων με βασική υπηρεσία την επεξεργασία απλών ερωτημάτων, σύντομα εξελίχτηκαν σε ένα καινούργιο μοντέλο κατανεμημένων συστημάτων, με μεγάλες και αυξανόμενες δυνατότητες για διαδικτυακές εφαρμογές, υποστηρίζοντας πολύπλοκες εφαρμογές διαμοιρασμού δομημένων και σημασιολογικά προσδιορισμένων δεδομένων. Η προσέγγισή μας στην περιοχή αυτή γίνεται προς δύο βασικές κατευθύνσεις: (α) την επεξεργασία πολύπλοκων ερωτημάτων και (β) την εκτίμηση των ανομοιομορφιών των διαφόρων κατανομών που συναντάμε στα δίκτυα αυτά (π.χ. φορτίου, προσφοράς ή κατανάλωσης ενός πόρου, τιμών των δεδομένων των κόμβων, κ.λπ.), που εκτός των άλλων αποτελεί ένα σημαντικό εργαλείο στην υποστήριξη πολύπλοκων ερωτημάτων. Συγκεκριμένα, ασχολούμαστε και επιλύουμε τρία βασικά ανοικτά προβλήματα. Το πρώτο ανοικτό πρόβλημα είναι η επεξεργασία ερωτημάτων εύρους τιμών σε ομότιμα συστήματα κατανεμημένου πίνακα κατακερματισμού, με ταυτόχρονη εξασφάλιση της εξισορρόπησης του φορτίου των κόμβων και της ανοχής σε σφάλματα. Προτείνουμε μια αρχιτεκτονική επικάλυψης, που ονομάζουμε Saturn, που εφαρμόζεται πάνω από ένα δίκτυο κατανεμημένου πίνακα κατακερματισμού. Η αρχιτεκτονική Saturn χρησιμοποιεί: (α) μια πρωτότυπη συνάρτηση κατακερματισμού που τοποθετεί διαδοχικές τιμές δεδομένων σε γειτονικούς κόμβους, για την αποδοτική επεξεργασία των ερωτημάτων εύρους τιμών και (β) την αντιγραφή, για την εξασφάλιση της εξισορρόπησης του φορτίου προσπελάσεων (κάθετη, καθοδηγούμενη από το φορτίο αντιγραφή) και της ανοχής σε σφάλματα (οριζόντια αντιγραφή). Μέσα από μια εκτεταμένη πειραματική αξιολόγηση του Saturn και σύγκριση με δύο βασικά δίκτυα κατανεμημένου πίνακα κατακερματισμού (Chord και OP-Chord) πιστοποιούμε την ανωτερότητα του Saturn να αντιμετωπίζει και τα τρία ζητήματα που θέσαμε, αλλά και την ικανότητά του να συντονίζει το βαθμό αντιγραφής ώστε να ανταλλάζει ανάμεσα στο κόστος αντιγραφής και στο βαθμό εξισορρόπησης του φορτίου. Το δεύτερο ανοικτό πρόβλημα που αντιμετωπίζουμε αφορά την έλλειψη κατάλληλων μετρικών που να εκφράζουν τις ανομοιομορφίες των διαφόρων κατανομών (όπως, για παράδειγμα, το βαθμό δικαιοσύνης μιας κατανομής φορτίου) σε κατανεμημένα δίκτυα κλίμακας Ίντερνετ και την μη αποτελεσματική ή δυναμική εκμετάλλευση μετρικών ανομοιομορφίας σε συνδυασμό με αλγορίθμους διόρθωσης (όπως ο αλγόριθμος εξισορρόπησης φορτίου). Το πρόβλημα είναι σημαντικό γιατί η εκτίμηση των κατανομών συντελεί στην ικανότητα κλιμάκωσης και στην επίδοση αυτών των δικτύων. Αρχικά, προτείνουμε τρεις μετρικές ανομοιομορφίας (το συντελεστή του Gini, τον δείκτη δικαιοσύνης και το συντελεστή διασποράς) μετά από μια αναλυτική αξιολόγηση μεταξύ γνωστών μετρικών εκτίμησης ανομοιομορφίας και στη συνέχεια, αναπτύσσουμε τεχνικές δειγματοληψίας (τρεις γνωστές τεχνικές και τρεις προτεινόμενες) για τη δυναμική εκτίμηση αυτών των μετρικών. Με εκτεταμένα πειράματα αξιολογούμε συγκριτικά τους προτεινόμενους αλγορίθμους εκτίμησης και τις τρεις μετρικές και επιδεικνύουμε πώς αυτές οι μετρικές και ειδικά, ο συντελεστής του Gini, μπορούν να χρησιμοποιηθούν εύκολα και δυναμικά από υψηλότερου επιπέδου αλγορίθμους, οι οποίοι μπορούν τώρα να ξέρουν πότε να επέμβουν για να διορθώσουν τις άδικες κατανομές. Το τρίτο και τελευταίο ανοικτό πρόβλημα αφορά την εκτίμηση του μεγέθους αυτοσύνδεσης μιας σχέσης όπου οι πλειάδες της είναι κατανεμημένες σε κόμβους δεδομένων που αποτελούν ένα ομότιμο δίκτυο επικάλυψης. Το μέγεθος αυτοσύνδεσης έχει χρησιμοποιηθεί εκτεταμένα σε συγκεντρωτικές βάσεις δεδομένων για τη βελτιστοποίηση ερωτημάτων και υποστηρίζουμε ότι μπορεί να χρησιμοποιηθεί και σε ένα πλήθος άλλων εφαρμογών, ειδικά στα ομότιμα δίκτυα (π.χ. συσταδοποίηση του Ιστού, αναζήτηση στον Ιστό, κ.λπ.). Η συνεισφορά μας περιλαμβάνει, αρχικά, τις προσαρμογές πέντε γνωστών συγκεντρωτικών τεχνικών εκτίμησης του μεγέθους αυτοσύνδεσης (συγκεκριμένα, σειριακή, ετεροδειγματοληπτική, προσαρμοστική και διεστιακή δειγματοληψία και δειγματοληψία με μέτρηση δείγματος) στο περιβάλλον ομοτίμων εταίρων και η ανάπτυξη μια πρωτότυπης τεχνικής εκτίμησης του μεγέθους αυτοσύνδεσης, βασισμένη στο συντελεστή του Gini. Με μαθηματική ανάλυση δείχνουμε ότι οι εκτιμήσεις του συντελεστή του Gini μπορούν να οδηγήσουν σε εκτιμήσεις των υποκείμενων κατανομών δεδομένων, όταν αυτά ακολουθούν το νόμο της δύναμης ή το νόμο του Zipf και αυτές, με τη σειρά τους, σε εκτιμήσεις του μεγέθους αυτοσύνδεσης των σχέσεων των δεδομένων. Μετά από αναλυτική πειραματική μελέτη και σύγκριση όλων των παραπάνω τεχνικών αποδεικνύουμε ότι η καινούργια τεχνική που προτείνουμε είναι πολύ αποτελεσματική ως προς την ακρίβεια, την πιστότητα και την απόδοση έναντι των άλλων πέντε μεθόδων.
The distributed, Internet-scale networks, and mainly, the peer-to-peer networks (p2p), that constitute their most representative example, recently attract a great interest from the researchers and the industry, due to their outstanding properties, such as full decentralization, autonomy of nodes, scalability, etc. Initially designed to support file sharing applications with simple lookup operations, they soon developed in a new model of distributed systems, with many and increasing possibilities for Internet applications, supporting complex applications of structured and semantically rich data. Our research to the area has two basic points of view: (a) complex query processing and (b) estimation of skewness in various distributions existing in these networks (e.g. load distribution, distribution of offer, or consumption of resources, data value distributions, etc), which, among others, it is an important tool to complex query processing support. Specifically, we deal with and solve three basic open problems. The first open problem is range query processing in p2p systems based on distributed hash tables (DHT), with simultaneous guarantees of access load balancing and fault tolerance. We propose an overlay DHT architecture, coined Saturn. Saturn uses a novel order-preserving hash function that places consecutive data values in successive nodes to provide efficient range query processing, and replication to guarantee access load balancing (vertical, load-driven replication) and fault tolerance (horizontal replication). With extensive experimentation, we evaluate and compare Saturn with two basic DHT networks (Chord and OP - Chord), and certify its superiority to cope with the three above requirements, but also its ability to tune the degree of replication to trade off replication costs for access load balancing. The second open problem that we face concerns the lack of appropriate metrics to express the degree of skewness of various distributions (for example, the fairness degree of load balancing) in p2p networks, and the inefficient and offline-only exploitation of metrics of skewness, which does not enable any cooperation with corrective algorithms (for example, load balancing algorithms). The problem is important because estimation of distribution fairness contributes to system scalability and efficiency. First, after a comprehensive study and evaluation of popular metrics of skewness, we propose three of them (the coefficient of Gini, the fairness index, and the coefficient of variation), and, then, we develop sampling techniques (three already known techniques, and three novel ones) to dynamically estimate these metrics. With extensive experimentation, which comparatively evaluates both the various proposed estimation algorithms and the three metrics we propose, we show how these three metrics, and especially, the coefficient of Gini, can be easily utilized online by higher-level algorithms, which can now know when to best intervene to correct unfairness. The third and last open problem concerns self-join size estimation of a relation whose tuples are distributed over data nodes which comprise an overlay network. Self-join size has been extensively used in centralized databases for query optimization purposes, and we support that it can also be used in various other applications, specifically in p2p networks (e.g. web clustering, web searching, etc). Our contribution first includes the adaptations of five well-known self-join size estimation, centralized techniques (specifically, sequential sampling, cross-sampling, adaptive and bifocal sampling, and sample-count) to the p2p environment and a novel estimation technique which is based on the Gini coefficient. With mathematical analysis we show that, the estimates of the Gini coefficient can lead to estimates of the degree of skewness of the underlying data distribution, when these follow the power, or Zipf’s law, and these estimates can lead to self-join size estimates of those data relations. With extensive experimental study and comparison of all above techniques, we prove that the proposed technique is very efficient in terms of accuracy, precision, and cost of estimation against the other five methods.